The invention concerns a combination pile wall, and more particularly a pile wall comprising a plurality of adjacent pile wall beam elements interconnected by connecting elements and possibly also sheet pile elements.
Combination pile walls of the aforesaid type are known from DE 297 18 052 U1, EP 0 072 118 A1, or also DE 103 18 769 A1; they are used to reinforce banks of harbors and rivers, to support a dam, or to erect quay walls and the like. The known combination pile walls are formed of beam elements such as double-T beams (I-beams), with connection shaped strips (connecting elements) connected directly to them which are intended to ensure at least an approximately watertight seal between the beam elements. The shaped connection strips are equipped with locking elements that engage with matching locking elements on the beam elements. If the loads on the combination pile walls from the soil are moderate, at least one sheet pile, called a “fill pile”, is positioned between each pair of adjacent beam elements so that the number of beam elements used in the pile wall, that are responsible for the resistance moment of the wall, may be reduced. In order to form a locked, water-tight pile wall, the sheet piles are also coupled together along their longitudinal edges by locking elements such as hook or claw strips, while the sheet piles positioned directly adjacent to the beam elements are connected with the beam elements by means of the shaped connection strips. The shaped connection strips are also equipped with suitable locking elements for this purpose.
The problem with known combination pile walls is that the locking elements engaged with one another are either so manufactured that they may hardly move with respect to one another, or the locking elements are so shaped that they may pivot over a wide angular range of up to ±45°. If the individual beam elements between which sheet piles are positioned as necessary are driven into the ground, there is a danger that, for those joints in which the locking elements allow practically no movement with respect to one another, the locking elements will become disengaged at least in sections or that the joints will break completely. On the one hand, this causes the vertical stability and stiffness of the overall combination pile wall to be negatively influenced while, on the other, it allows passage of water through the combination pile wall because the sections are damaged or are no longer engaged. If, in contrast, combination pile walls are used where the locking elements allow large pivot angles, the beam elements and sheet piles may deviate from each other when driven into the ground, moving out of their intended positions, so that an exact positioning of the combination pile wall is made more difficult.